Question

According to Gartner Inc., the largest share of the worldwide PC market is held by Hewlett-Packard with 16.0%. Suppose that a market researcher believes that Hewlett-Packard holds a higher share of the market in the western region of the United States. To verify this theory, he randomly selects 428 people who purchased a personal computer in the last month in the western region of the United States. Seventy-four of these purchases were Hewlett-Packard computers. Using a 1% level of significance, test the market researcher’s theory. If the market share is really .19 in the southwestern region of the United States, what is the probability of making a Type II error?